Mark McCallum will never forget the first time he was acknowledged in a scientific journal.

He printed the article out and said to his wife and eight-year-old son: "Look at that, Dad's on a scientific paper".

But McCallum isn't a professional scientist, he's an Aussie 'pea hunter'.

Through participating in a project called Galaxy Zoo, with thousands of other people around the globe, McCallum helped discover a group of rare galaxies that are forming stars 10 times faster than the Milky Way.

Because of the galaxies' size and shape they were dubbed the 'green peas'.

McCallum and his fellow Zooites are part of a growing number of ordinary people taking part in scientific research through so-called 'citizen science' projects.

For many their motivation is simple: you feel like you are contributing to real science, says McCallum.

And with an increasing number of projects available across a range of scientific disciplines there's never been a better time to join their ranks.

The rise of citizen science

Citizen science isn't new. Australian citizen scientists provided British naturalist John Gould with many of the specimens illustrated in his 1848 The Birds of Australia series.

One of the world's longest-running citizen science projects, the National Audubon Society's Christmas Bird Count in the United States, started in 1900.

But the popularity and scope of citizen science projects has really taken off with the rise of the internet.

"Clearly in the last few years these sorts of opportunities have been greatly facilitated by social networks and [the] collaborative tools that we've seen with Web 2.0," says Dr Liz Lyon, director of UKOLN at the University of Bath, who has been leading research into open science environments.

With the way that citizen journalism has enriched reporting, Lyon thinks there's a lot that scientists could learn from citizen journalists.

Not only does citizen science raise public awareness of science it also exposes people to aspects of the way it's done, "perhaps in some ways demystifying it" she says.

It also allows scientists an alternative way to do some of the things they may want to do but can't fund.

"Certainly if we want to get a better idea of how our environment works to inform discussions about global warming, climate change and so on," says Lyon. "The more data we have… provided it's reasonable data, then I think that's going to help."

SETI@home: Is that ET calling?

First launched in May 1999, SETI@home requires users to install a free program on their computer that downloads and analyses packages of radio telescope data via the internet.

Using the computer's leftover processing power, the program looks for narrow-bandwidth radio signals from space. Not known to occur naturally these signals could provide evidence of extraterrestrial intelligence.

For the project's director Dr David Anderson at the University of California, Berkley the continuing success of SETI@home lies in people's desire to understand their place in the universe.

"This leads directly to the question of whether life exists outside Earth," says Anderson. "Many people regard this as the most important unanswered (but potentially answerable) question."

Taking part in SETI@home allows people to have a say in what scientific research is done, he says.

"It makes them stakeholders in science, rather than observers."

The software that underpins SETI@home was extended to other science disciplines from climate change to cancer research with the launch of the BOINC project in 2002.

"These days there are about 60 BOINC-based projects doing research in a wide range of areas," says Anderson.

So not only can you take part in whatever project you like, there's also the opportunity to forms teams and compare your performance against other users, like in the Rosetta@home project on protein folding which encourages users to "solve puzzles for science".

Anderson is also working on another software development project, called Bossa, to provide support for volunteer thinking projects that use human intelligence not computer processing power.

Operation animals change attitudes

Brushtail possums were one of the species surveyed by Operation Possum.
(Source: Barbara Hardy Centre for Sustainable Urban Environments)

If actually going out and collecting data in the field sounds more like the sort of science you want to be involved in, there are projects for that too.

Professor Chris Daniels, the director of the Barbara Hardy Centre for Sustainable Urban Environments at the University of South Australia, has been running surveys looking at the distribution and behaviour of particular animals and people's attitudes towards them since 2007 in partnership with ABC Local Radio Adelaide.

So far South Australians have told him how they feel about bluetongue lizards, possums and magpies, as well as provided good biological data on how these animals live in urban areas. And they're now in the planning stages of Operation Spider.

"People need a fair amount of information and guidance but they can be very good data collectors," says Daniels.

Recruiting members of the public to collect data has also had some benefits.

"[Prior to Operation Bluetongue] we couldn't actually do habitat utilisation, or food or dietary preferences or anything on bluetongues in people's backyards because you can't get permission to get into them," he says.

But Daniels says using citizen scientists also brings with it certain responsibilities.

"If you're going to do citizen science you have to give the results back to people."

So far they've published one book on their research and people's stories about the animals they observed, with two more in the pipeline.

ClimateWatch: local research contributes to global policy

The dearth of Australian data about how plants and animals are responding to climate change inspired not-for-profit organisation EarthWatch to create a citizen science project called ClimateWatch.

"The IPCC report from 2007 published the fact that there's something like 29,000 data sets in the world on the response of biological systems to climate," says Andy Donnelly, Earthwatch's science partnerships director.

"In Australia there's six, none of which were nationally significant."

Drawing on similar examples in the Northern Hemisphere, Earthwatch looked for ways the community could contribute broad data sets that could be supplement scientists' existing data.

The result is ClimateWatch, which asks the community to observe regional and national species which could be affected by climate change.

"Climate change is a kind of intangible problem, the science is very complex, it's often inaccessible," Donnelly says.

"This is a way you can do climate change science, contribute to that… when you're gardening, when you go on a bushwalk, when you go to work."

The ultimate aim of the project is that the community-generated data will be used at the highest policy level.

The devil is in the data

Jacaranda trees are one of 50 species of plants and animals being monitored by the ClimateWatch program.
(Source: Tatiana Gerus/Earthwatch)

Not all research lends itself to the citizen science approach, however, particularly more technical areas of science. And some scientists may be reluctant to trust data collected by non-specialists, concedes Lyon.

"This is a valid point, we need to have mechanisms to ensure that the research that comes out of these sort of activities maintains a high standard and is validated," she says.

There are many ways projects ensure their data is robust and reproducible.

ClimateWatch has a system which is able to automatically detect outliers in the data which can then be referred to monitors on the ground to check what is really happening at a particular location.

Galaxy Zoo has designed interfaces specifically for the public and collects multiple classifications of each galaxy they're looking at to ensure the small number of incorrect classifications don't distort their data. This also allows them to build up a more nuanced picture of how prominent the shape of a galaxy is.

And Daniels's team from the University of South Australia provides background information for participants and mechanisms by which they can contact experts with their problems or queries. They also include particular questions in their surveys to test when they've hit the limit of people's knowledge to ensure they get reproducible results.

It is also important to remember that delivering robust data is not the only aim of citizen science projects, says Daniels.

"Citizen science in biology is a very powerful form or engagement and attitudinal change… regardless of the scientific quality of the data," he says.

Citizen science goes mobile

One of the most exciting prospects for citizen science is the emerging opportunities presented by increasing use of mobile devices and development of smart phone applications for many projects from classifying galaxies to tracking cassowaries.

With a Galaxy Zoo app just around the corner, Lintott is confident increased access and some friendly competition will only help the project.

"What do you do if the person next to you [on the train] gets a more interesting galaxy than you? I think you just have to keep classifying."

With many devices now boasting GPS capabilities you can not only record data on the go but also have your phone automatically log where you were when you recorded it.

Researchers in the United States are taking this idea one step further by trialling mobile devices equipped with environmental sensors.

In the future these sensors could be used to take a range of environmental measurements from pollutant readings and pollen counts, to the ambient temperature of the street corner you're standing on.

Not only could these everyday devices contribute to data sets for professional research they could also allow people to improve life in cities, whether by being more aware of their own readings or using a collection of them to plot clean air routes through a city.

Citizen science is not only changing the way we do and perceive science, it's also empowering people to make a difference, says Lyon.

Galaxy Zoo's Lintott agrees: "Anyone can make an actual contribution to what we know about the universe and I think that's quite an inspiring thought."

We'll leave the rest up to you.

Share your citizen science experiences on our message board.

Get involvedInterested in becoming a scientist? There are new projects springing up every day, here are just a few to choose from:

zeff :

Joseph K.H. Cheng :

20 Apr 2010 11:08:50am

This is a great article done in a lively manner. It covers all aspects of citizen science which, in my humble opinion, is the future trend for scientific research especially for under funded projects. As regards Galaxy Zoo which is my pet project I will just say that there is great potential there for educating the younger generation. They should be encouraged to join this useful and satisfying project as a productive hobby.I raise my hat to the ZOO TEAM and all Zooites. Thanks, ABC Science for publishing such a high quality feature and congratulations to Suzannah for her professionalism. Keep up the good work !

Heather :

21 Apr 2010 12:39:35am

This was a great article! A little long, but well worth the read :-) For any one is interested, the Earth Watch Institute also conducts a variety of volunteer research expeditions (not just ClimateWatch). Go to earthwatch.org for more details. I'm hoping to join an expedition in 2011--it's a great way to get involved with science, learn about the world around us, and donate our time to something meaningful.

Belinda Weaver :

23 Feb 2012 5:00:06pm

The Zooniverse also encompasses a number of projects that would draw in non-scientists - it is not all astronomy. There is one that looks at ancient texts and another about digitising old shipping records. People can also get involved in transcription projects like the Bentham Project and the Civil War diaries where they help create digital versions of handwritten manuscripts and letters. Something for everyone!